/*
 * Copyright (C) 2010, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR
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 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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#ifndef SKY_ENGINE_WTF_TEXT_TEXTPOSITION_H_
#define SKY_ENGINE_WTF_TEXT_TEXTPOSITION_H_

#include "flutter/sky/engine/wtf/Assertions.h"
#include "flutter/sky/engine/wtf/Vector.h"
#include "flutter/sky/engine/wtf/WTFExport.h"
#include "flutter/sky/engine/wtf/text/WTFString.h"

namespace WTF {

// An abstract number of element in a sequence. The sequence has a first
// element. This type should be used instead of integer because 2 contradicting
// traditions can call a first element '0' or '1' which makes integer type
// ambiguous.
class OrdinalNumber {
 public:
  static OrdinalNumber fromZeroBasedInt(int zeroBasedInt) {
    return OrdinalNumber(zeroBasedInt);
  }
  static OrdinalNumber fromOneBasedInt(int oneBasedInt) {
    return OrdinalNumber(oneBasedInt - 1);
  }
  OrdinalNumber() : m_zeroBasedValue(0) {}

  int zeroBasedInt() const { return m_zeroBasedValue; }
  int oneBasedInt() const { return m_zeroBasedValue + 1; }

  bool operator==(OrdinalNumber other) {
    return m_zeroBasedValue == other.m_zeroBasedValue;
  }
  bool operator!=(OrdinalNumber other) { return !((*this) == other); }

  static OrdinalNumber first() { return OrdinalNumber(0); }
  static OrdinalNumber beforeFirst() { return OrdinalNumber(-1); }

 private:
  OrdinalNumber(int zeroBasedInt) : m_zeroBasedValue(zeroBasedInt) {}
  int m_zeroBasedValue;
};

// TextPosition structure specifies coordinates within an text resource. It is
// used mostly for saving script source position.
class TextPosition {
 public:
  TextPosition(OrdinalNumber line, OrdinalNumber column)
      : m_line(line), m_column(column) {}
  TextPosition() {}
  bool operator==(const TextPosition& other) {
    return m_line == other.m_line && m_column == other.m_column;
  }
  bool operator!=(const TextPosition& other) { return !((*this) == other); }
  WTF_EXPORT OrdinalNumber toOffset(const Vector<unsigned>&);

  // A 'minimum' value of position, used as a default value.
  static TextPosition minimumPosition() {
    return TextPosition(OrdinalNumber::first(), OrdinalNumber::first());
  }

  // A value with line value less than a minimum; used as an impossible
  // position.
  static TextPosition belowRangePosition() {
    return TextPosition(OrdinalNumber::beforeFirst(),
                        OrdinalNumber::beforeFirst());
  }

  // A value corresponding to a position with given offset within text having
  // the specified line ending offsets.
  WTF_EXPORT static TextPosition fromOffsetAndLineEndings(
      unsigned,
      const Vector<unsigned>&);

  OrdinalNumber m_line;
  OrdinalNumber m_column;
};

WTF_EXPORT PassOwnPtr<Vector<unsigned>> lineEndings(const String&);

}  // namespace WTF

using WTF::OrdinalNumber;

using WTF::TextPosition;

using WTF::lineEndings;

#endif  // SKY_ENGINE_WTF_TEXT_TEXTPOSITION_H_
